Choshin (1014 - November 12, 1072) was a Buddhist monk of the Shingon sect, in the mid-Heian period. His father was FUJIWARA no Michinaga, a Sessho (regent). His mother was a daughter of a Dainagon (chief councilor of state), MINAMOTO no Shigemitsu, who was a child of Imperial Prince Yoshiakira. He also went by the name Ikebe Sojo.
He became a disciple of Enjin, who was a child of MINAMOTO no Sukenori in Kannon-in of Ninna-ji Temple, and became a priest there, whereupon he received kanjo (a ceremony to be the successor) by priest-Imperial Prince Shoshin in 1047. In 1049, he moved to To-ji Temple and became gon shosozu (junior lesser prelate), isshin-ajari (a special class of teaching priests who were noble and permitted to play the role of ajari). In 1054, he was appointed as the twenty-ninth choja of To-ji Temple, who was the chief abbot of the temple and the entire Shingon sect, and was promoted to hoin (the highest rank among Buddhist priests). In 1066, he became gon no sojo (the highest-ranking priest next to a sojo) and performed a ritual for rain along with 20 priests on behalf of relief from that year's drought. In 1070, he was appointed as Sojo, and in the following year he erected 'Ikenobo' in the territory of To-ji Temple and lived there. He had been in the close confidence of Emperor Gosanjo, who visited Chosin with all his officials that year and granted fuko (a vassal household allotted to courtiers, shrines and temples) 25 households. He served as betto (intendant) in such temples as Ninna-ji Temple.